Owing to the vdW gaps between clusters, their conductivity is expected to be
low and thus they should be fairly good insulators even though their band gaps in
the crystalline form are not very high.
Consequently, “metallic” 0D materials do not appear particularly promising
as electrode materials.
In addition to their use as a gate dielectric or substrate,
these 0D materials could be used as spacer layers in 2D material superlattices [1]}.
Intercalation between 2D layers can also stabilize crystalline order for clusters
that have too low melting point in 3D lattice.
For instance, superlattices of 2D materials and CTAB (and other related) molecules
was demonstrated in [2]}.
Also, AlCl3 and CuCl2 clusters
and various dimerized and trimerized forms of them have successfully been
intercalated between graphene sheets [3]}.
Although materials consisting of more than one type of clusters were
ignored in this Letter for reasons of simplicity, a vast variety of
such 0D molecular compounds could exist.
As an example, 2D crystal made of SbI3 and S8 molecular units
was reported in Ref. [4]}.
